PMID- 10026142
OWN - NLM
STAT- MEDLINE
DCOM- 19990318
LR  - 20190508
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 274
IP  - 9
DP  - 1999 Feb 26
TI  - Purification and identification of a novel subunit of protein serine/threonine
      phosphatase 4.
PG  - 5339-47
AB  - The catalytic subunit of protein serine/threonine phosphatase 4 (PP4C) has
      greater than 65% amino acid identity to the catalytic subunit of protein
      phosphatase 2A (PP2AC). Despite this high homology, PP4 does not appear to
      associate with known PP2A regulatory subunits. As a first step toward
      characterization of PP4 holoenzymes and identification of putative PP4 regulatory
      subunits, PP4 was purified from bovine testis soluble extracts. PP4 existed in
      two complexes of approximately 270-300 and 400-450 kDa as determined by gel
      filtration chromatography. The smaller PP4 complex was purified by sequential
      phenyl-Sepharose, Source 15Q, DEAE2, and Superdex 200 gel filtration
      chromatographies. The final product contained two major proteins: the PP4
      catalytic subunit plus a protein that migrated as a doublet of 120-125 kDa on
      SDS-polyacrylamide gel electrophoresis. The associated protein, termed PP4R1, and
      PP4C also bound to microcystin-Sepharose. Mass spectrometry analysis of the
      purified complex revealed two major peaks, at 35 (PP4C) and 105 kDa (PP4R1).
      Amino acid sequence information of several peptides derived from the 105 kDa
      protein was utilized to isolate a human cDNA clone. Analysis of the predicted
      amino acid sequence revealed 13 nonidentical repeats similar to repeats found in 
      the A subunit of PP2A (PP2AA). The PP4R1 cDNA clone engineered with an N-terminal
      Myc tag was expressed in COS M6 cells and PP4C co-immunoprecipitated with
      Myc-tagged PP4R1. These data indicate that one form of PP4 is similar to the core
      complex of PP2A in that it consists of a catalytic subunit and a "PP2AA-like"
      structural subunit.
FAU - Kloeker, S
AU  - Kloeker S
AD  - Department of Pharmacology, Vanderbilt University Medical Center, Nashville,
      Tennessee 37232-6600, USA.
FAU - Wadzinski, B E
AU  - Wadzinski BE
LA  - eng
SI  - GENBANK/AF111106
GR  - CA68485/CA/NCI NIH HHS/United States
GR  - DK20593/DK/NIDDK NIH HHS/United States
GR  - GM51366/GM/NIGMS NIH HHS/United States
GR  - etc.
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (DNA, Complementary)
RN  - EC 3.1.3.16 (Phosphoprotein Phosphatases)
RN  - EC 3.1.3.16 (Protein Phosphatase 2)
RN  - EC 3.1.3.16 (protein phosphatase 4)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Base Sequence
MH  - COS Cells
MH  - Catalytic Domain
MH  - Cattle
MH  - Chromatography, Gel
MH  - Chromatography, Ion Exchange
MH  - DNA, Complementary
MH  - Humans
MH  - Male
MH  - Mass Spectrometry
MH  - Molecular Sequence Data
MH  - Phosphoprotein Phosphatases/genetics/isolation & purification/*metabolism
MH  - Precipitin Tests
MH  - Protein Phosphatase 2
MH  - Testis/enzymology
EDAT- 1999/02/20 00:00
MHDA- 1999/02/20 00:01
CRDT- 1999/02/20 00:00
PHST- 1999/02/20 00:00 [pubmed]
PHST- 1999/02/20 00:01 [medline]
PHST- 1999/02/20 00:00 [entrez]
AID - 10.1074/jbc.274.9.5339 [doi]
PST - ppublish
SO  - J Biol Chem. 1999 Feb 26;274(9):5339-47. doi: 10.1074/jbc.274.9.5339.